Some of brake control apparatuses mounted on vehicles, such as four-wheeled automobiles, are configured to variably control a brake hydraulic pressure to be generated in a master cylinder to supply brake fluid to a wheel cylinder of the vehicle with use of an electric motor or the like. This kind of brake apparatus is configured to calculate an amount by which a driver operates a brake pedal, and switch control between positional control and hydraulic control as necessary. In the positional control, the brake control apparatus controls a rotation of the electric motor in such a manner that a relative displacement between an input member coupled to the brake pedal and a primary piston of the master cylinder matches a preset target relative displacement. In the hydraulic control, the brake control apparatus controls the rotation of the electric motor in such a manner that a hydraulic pressure in the master cylinder matches a preset target hydraulic pressure with respect to the amount by which the brake pedal is operated (for example, refer to PTL 1).